JP2018123876A - Control device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an automatic transmission capable of suppressing a variation of a vehicle behavior due to an upshift of a sub-transmission mechanism regardless of a determination result of power-on or power-off.SOLUTION: The control device of an automatic transmission performs power-off upshift control regardless of torque information when a sub-transmission mechanism is upshifted in a first region which is a vehicle speed range being equal to or more than a first vehicle speed at which a first mode switching line for upshifting the sub-transmission mechanism at a low accelerator pedal opening degree is set and being equal to or less than a second vehicle speed at which a second mode switching line for upshifting the sub-transmission mechanism at a high accelerator pedal opening degree i set, and is defined by a rotation speed range which is equal to or more than a main transmission mechanism input rotating speed of a coast line with a target transmission gear ratio set during coast travel, and is equal to or less than a main transmission mechanism input rotating speed corresponding to the first mode switching line in a third vehicle speed at which the lowest line and a coast line are crossed when the sub-transmission mechanism selects a high side gear position in the mode switching line during the low accelerator pedal opening degree.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a control device for an automatic transmission including a sub-transmission mechanism and a continuously variable transmission mechanism.

  As a control device for an automatic transmission provided with a sub-transmission mechanism and a continuously variable transmission mechanism, the technology of Patent Document 1 is known. In this publication, when the speed ratio of the automatic transmission (hereinafter referred to as a through speed ratio) obtained from both the speed ratio of the subtransmission mechanism and the speed ratio of the continuously variable transmission mechanism is shifted, the subtransmission mechanism When an upshift is involved, control during power-on upshifting when the torque input from the engine side is positive torque in the auxiliary transmission mechanism and upshifting when the torque input from the engine side is negative torque The control during the power-off upshift is disclosed.

JP 2010-209948 A

  Here, since the start timing of the inertia phase differs between the power-on upshift and the poweroff upshift, if the determination of power-on or power-off is wrong, the shift timing on the continuously variable transmission side and the shift timing on the auxiliary transmission mechanism side The through speed ratio may change to the upshift side and the engine speed may decrease. When the engine speed decreases, it is necessary to release the lock-up clutch in order to avoid engine stall, and there is a possibility that the driver feels uncomfortable by affecting the vehicle behavior.

  The present invention focuses on the above-described problem, and an object thereof is to provide a control device for an automatic transmission that can suppress fluctuations in vehicle behavior associated with an upshift of a sub-transmission mechanism regardless of power-on or power-off determination results. To do.

  For this purpose, in the automatic transmission control device of the present invention, an automatic transmission having a main transmission mechanism capable of continuously changing a transmission gear ratio, and a sub-transmission mechanism having a plurality of fixed shift stages,

  A target transmission ratio of the automatic transmission is calculated, and the main transmission mechanism and the auxiliary transmission mechanism are configured to achieve the target transmission ratio by combining the transmission ratio of the main transmission mechanism and the transmission ratio of the auxiliary transmission mechanism. A controller for controlling a transmission ratio, and the controller determines whether the input torque of the automatic transmission is in a power-on state or a power-off state based on torque information received from the engine, and When upshifting the auxiliary transmission mechanism, power-on upshift control is performed to shift from the torque phase to the inertia phase. When in the power-off state, torque is applied from the inertia phase when upshifting the auxiliary transmission mechanism. Perform power off upshift control to shift to the phase and upshift the auxiliary transmission mechanism at low accelerator pedal opening A vehicle speed range that is equal to or higher than the first vehicle speed at which the first mode switching line is set and is below the second vehicle speed at which the second mode switching line for upshifting the auxiliary transmission mechanism with a high accelerator pedal opening is set, and coasting The target transmission gear ratio is equal to or greater than the input speed of the main transmission mechanism on the coast line set, and the auxiliary transmission mechanism selects the high-side gear position among the low accelerator pedal opening mode switching lines. In the first region defined by the rotational speed range equal to or less than the input speed of the main transmission mechanism corresponding to the first mode switching line at the third vehicle speed at which the lowest line and the coast line intersect, the auxiliary transmission mechanism When upshifting, the power-off upshift control is performed regardless of the torque information.

  Therefore, regardless of the power-on or power-off determination result, it is possible to suppress a decrease in the engine speed associated with the upshift of the subtransmission mechanism, and to avoid the release of the lockup clutch, thereby suppressing the fluctuation in vehicle behavior.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic system diagram showing a vehicle drive system and its overall control system according to a first embodiment. In the vehicle of the first embodiment, (a) is a schematic system diagram showing a drive system of the vehicle and an overall control system thereof, and (b) is incorporated in a V-belt continuously variable transmission in the drive system of the vehicle. FIG. 6 is a logic diagram for engaging a clutch in the auxiliary transmission. 3 is an example of a shift map stored in the transmission controller according to the first embodiment. 5 is a time chart showing a shift state when the vehicle speed of the first embodiment crosses the low accelerator pedal opening mode switching line due to an increase in vehicle speed. In the vehicle of a comparative example, it is a time chart showing the shift state at the time of crossing the mode change line at the time of the low accelerator pedal opening by the release of the accelerator pedal. 4 is a flowchart illustrating an upshift process by straddling a mode switching line according to the first embodiment. 5 is a time chart showing a shift state when the low accelerator pedal opening mode switching line is crossed by releasing the accelerator pedal opening in the vehicle of the first embodiment.

[Example 1]
FIG. 1 is a schematic system diagram showing a vehicle drive system and its overall control system according to a first embodiment. The vehicle shown in FIG. 1 is equipped with an engine 1 as a power source. The engine 1 is started by the starter motor 3. The engine 1 is drive-coupled to the drive wheels 5 via the automatic transmission 4 so as to be appropriately separable.

  The variator CVT of the automatic transmission 4 is a V-belt type continuously variable transmission mechanism including a primary pulley 6, a secondary pulley 7, and a V-belt 8 (endless flexible member) spanned between the pulleys 6 and 7. . The V belt 8 employs a configuration in which a plurality of elements are bundled by an endless belt, but may be a chain system or the like, and is not particularly limited. The primary pulley 6 is coupled to the crankshaft of the engine 1 via the torque converter T / C, and the secondary pulley 7 is coupled to the drive wheel 5 via the clutch CL and the final gear set 9 in order. In the present embodiment, elements (such as a clutch and a brake) that connect and disconnect the power transmission path are collectively referred to as a clutch. FIG. 1 conceptually shows a power transmission path. A high clutch H / C, a reverse brake R / B, and a low brake L / B provided in an auxiliary transmission 31 described later are collectively referred to as a clutch. It is described as CL. When the clutch CL is engaged, the power from the engine 1 is input to the primary pulley 6 via the torque converter T / C, and then sequentially passes through the V belt 8, the secondary pulley 7, the clutch CL, and the final gear set 9 to drive wheels 5 And drive.

  During engine power transmission, the pulley V groove width of the primary pulley 6 is reduced while the pulley V groove width of the secondary pulley 7 is increased to increase the winding arc diameter of the V belt 8 and the primary pulley 6 and at the same time Decrease the diameter of the winding arc with pulley 7. As a result, the variator CVT upshifts to the high pulley ratio (high gear ratio). When the upshift to the High side gear ratio is performed to the limit, the gear ratio is set to the maximum gear ratio.

  Conversely, by increasing the pulley V groove width of the primary pulley 6 and reducing the pulley V groove width of the secondary pulley 7, the winding pulley diameter of the V belt 8 and the primary pulley 6 is reduced, and at the same time the secondary pulley 7 Increase the winding arc diameter. As a result, the variator CVT downshifts to the low pulley ratio (low gear ratio). When downshifting to the low side gear ratio is performed to the limit, the gear shift is set to the minimum gear ratio.

  The variator CVT has a primary rotational speed sensor 6a for detecting the rotational speed of the primary pulley 6 and a secondary rotational speed sensor 7a for detecting the rotational speed of the secondary pulley 7, and the rotational speed detected by these both rotational speed sensors. The actual CVT speed ratio Iv is calculated based on the above, and hydraulic control of each pulley is performed so that the actual CVT speed ratio Iv becomes the target CVT speed ratio Iv *.

  The engine controller 22 controls the output of the engine 1, and the transmission controller 24 uses the oil from the engine-driven mechanical oil pump O / P as a medium to control the shift of the variator CVT and the shift control of the auxiliary transmission 31. Engagement / release control of the clutch CL is performed.

  FIG. 2 (a) is a schematic system diagram showing the vehicle drive system and its overall control system according to the first embodiment, and FIG. 2 (b) is incorporated in the automatic transmission 4 in the vehicle drive system according to the first embodiment. FIG. 4 is an engagement logic diagram of a clutch CL (specifically, H / C, R / B, L / B) in the sub-transmission 31 that has been made. As shown in FIG. 2 (a), the auxiliary transmission 31 rotatably supports the composite sun gears 31s-1 and 31s-2, the inner pinion 31pin, the outer pinion 31pout, the ring gear 31r, and the pinions 31pin and 31pout. And a Ravigneaux type planetary gear set comprising the carrier 31c.

  Of the composite sun gears 31s-1 and 31s-2, the sun gear 31s-1 is coupled to the secondary pulley 7 so as to act as an input rotating member, and the sun gear 31s-2 is arranged coaxially with respect to the secondary pulley 7, but freely rotates. To get.

The inner pinion 31pin is engaged with the sun gear 31s-1, and the inner pinion 31pin and the sun gear 31s-2 are respectively engaged with the outer pinion 31pout.
The outer pinion 31pout meshes with the inner periphery of the ring gear 31r, and is coupled to the final gear set 9 so that the carrier 31c acts as an output rotating member.
The carrier 31c and the ring gear 31r can be appropriately coupled by the high clutch H / C as the clutch CL, the ring gear 31r can be appropriately fixed by the reverse brake R / B as the clutch CL, and the sun gear 31s-2 can be coupled by the clutch CL. It can be fixed as appropriate with a certain low brake L / B.

  The auxiliary transmission 31 is engaged with the high clutch H / C, the reverse brake R / B, and the low brake L / B in the combinations indicated by the circles in FIG. 2 (b), and the others are shown in FIG. 2 (b). By releasing as shown by the mark, the forward first speed, the second speed, and the reverse speed can be selected. When the high clutch H / C, reverse brake R / B, and low brake L / B are all released, the sub-transmission 31 is in a neutral state where no power is transmitted. When the transmission 31 is in the first forward speed selection (deceleration) state and the high clutch H / C is engaged, the auxiliary transmission 31 is in the second forward speed selection (direct connection) state and when the reverse brake R / B is engaged, The transmission 31 is in a reverse selection (reverse) state.

  The automatic transmission 4 shown in FIG. 2 (a) releases the variator CVT (secondary pulley) by releasing all clutches CL (H / C, R / B, L / B) and setting the sub-transmission 31 in a neutral state. 7) and drive wheel 5 can be separated.

  The automatic transmission 4 in FIG. 2 (a) is controlled using oil from an engine-driven mechanical oil pump O / P as a working medium. The transmission controller 24 includes a line pressure solenoid 35, a lockup solenoid 36, and the like. The control of the variator CVT is controlled as follows through the primary pulley pressure solenoid 37-1, the secondary pulley pressure solenoid 37-2, the low brake pressure solenoid 38, the high clutch pressure & reverse brake pressure solenoid 39 and the switch valve 41. To do. The transmission controller 24 includes a signal from an accelerator pedal opening sensor 27 that detects an accelerator pedal depression amount (accelerator pedal opening) APO (see FIG. 1), a signal from a vehicle speed sensor 32 that detects a vehicle speed VSP, A signal from the acceleration sensor 33 that detects the vehicle acceleration / deceleration G is input.

The line pressure solenoid 35 responds to a command from the transmission controller 24 and regulates the oil from the mechanical oil pump O / P to the line pressure PL corresponding to the vehicle required driving force. The lockup solenoid 36 responds to a lockup command from the transmission controller 24 and directs the line pressure PL to the torque converter T / C as appropriate, so that the torque converter T / C is connected between the input and output elements as required. Set to a directly connected lockup state. The primary pulley pressure solenoid 37-1 adjusts the line pressure PL to the primary pulley pressure in response to the CVT gear ratio command from the transmission controller 24, and supplies this to the primary pulley 6, thereby The CVT gear ratio command from the transmission controller 24 is realized by controlling the groove width and the V groove width of the secondary pulley 7 so that the CVT gear ratio matches the command from the transmission controller 24. The secondary pulley pressure solenoid 37-2 adjusts the line pressure PL to the secondary pulley pressure in accordance with a clamping force command from the transmission controller 24, and supplies the secondary pulley pressure to the secondary pulley 7. Clamp it so that it will not slip.
The low brake pressure solenoid 38 is engaged by supplying the line pressure PL to the low brake L / B as the low brake pressure when the transmission controller 24 issues the first speed selection command for the sub-transmission 31. The first speed selection command is realized.
The high clutch pressure & reverse brake pressure solenoid 39 is a switch valve that uses the line pressure PL as the high clutch pressure & reverse brake pressure when the transmission controller 24 issues the second speed selection command or reverse selection command for the sub-transmission 31. Supply to 41.

At the time of the second speed selection command, the switch valve 41 uses the line pressure PL from the solenoid 39 as the high clutch pressure to the high clutch H / C, and by engaging this, the second speed selection command of the auxiliary transmission 31 is issued. Realize.
At the time of the reverse selection command, the switch valve 41 uses the line pressure PL from the solenoid 39 as the reverse brake pressure to the reverse brake R / B and fastens it, thereby realizing the reverse selection command of the auxiliary transmission 31.

[About shift control processing]
Next, the shift control process will be described. FIG. 3 is an example of a shift map stored in the transmission controller 24 of the first embodiment. The transmission controller 24 controls the automatic transmission 4 according to the driving state of the vehicle (vehicle speed VSP, primary rotational speed Npri, accelerator pedal opening APO in the first embodiment) while referring to this shift map. In this shift map, the operating point of the automatic transmission 4 is defined by the vehicle speed VSP and the primary rotational speed Npri (or the turbine rotational speed Nt). The slope of the line connecting the operating point of the automatic transmission 4 and the zero point of the lower left corner of the transmission map is the transmission ratio of the automatic transmission 4 (the overall ratio obtained by multiplying the transmission ratio Iv of the variator CVT by the transmission ratio Isub of the auxiliary transmission 31). Gear ratio Ith, hereinafter referred to as “through gear ratio”).

  Similar to the shift map of the conventional belt-type continuously variable transmission, a shift line is set for each accelerator pedal opening APO in this shift map, and the shift of the automatic transmission 4 depends on the accelerator pedal opening APO. According to the selected shift line. When the current operating point of the automatic transmission 4 crosses various shift lines set in the shift map, the shift starts from the current shift state to a new shift state set by crossing the shift line.

  When the automatic transmission 4 is in the low speed mode, the automatic transmission 4 can be obtained by setting the low speed mode lowest line obtained by setting the transmission ratio of the variator CVT to the lowest transmission ratio and the transmission ratio of the variator CVT being the highest transmission ratio. The speed can be changed between the highest line in the low speed mode. On the other hand, when the automatic transmission 4 is in the high speed mode, the automatic transmission 4 sets the speed ratio of the variator CVT to the highest gear ratio and the variator CVT to the highest gear ratio. It is possible to shift between the resulting high speed mode highest line.

  The gear ratio of each gear stage of the sub-transmission 31 is such that the gear ratio corresponding to the low speed mode highest line (low speed mode highest high gear ratio) corresponds to the high speed mode lowest line (high speed mode lowest gear ratio). It is set to be smaller than that.

  In addition, a plurality of mode switching shift lines for shifting the sub-transmission 31 are set on the shift map. When the driver does not greatly depress the accelerator pedal, a 1-2 upshift is performed in the mode switching shift line at the time of low accelerator pedal opening. This is because when the accelerator pedal opening is low, the input torque to the sub-transmission 31 is small even when the gear ratio of the variator CVT is large, and the shift shock when shifting the sub-transmission 31 is suppressed. In addition, the low-accelerator pedal opening-time mode switching shift line has a portion set on the lower side than the high-speed mode lowest line. This is a low speed overall including the engine 1, and since it is difficult to secure the speed of the variator CVT, a 1-2 upshift is started from this area. This is to ensure the shift time.

  On the other hand, the mode switching line at the time of the high accelerator pedal opening is set slightly lower than the low speed mode highest line. The mode change shift line for the high accelerator pedal position is set in this way because the input torque to the sub-transmission 31 decreases as the gear ratio of the variator CVT decreases, and the shift shock when shifting the sub-transmission 31 This is because it can be suppressed. The high accelerator pedal opening-time mode switching shift line has a portion set on the Low side of the low speed mode highest line. This is also set in consideration of the speed of the variator CVT and the speed of the inertia phase of the auxiliary transmission 31 in practice.

  When the operating point of the automatic transmission 4 crosses the mode switching shift line at the time of low accelerator pedal opening or at the time of high accelerator pedal opening, the transmission controller 24 performs coordinated shifting with both the variator CVT and the auxiliary transmission 31. Switching between high speed mode and low speed mode.

  FIG. 4 is a time chart showing a speed change state when the vehicle according to the first embodiment crosses the low accelerator pedal opening mode switching line due to an increase in the vehicle speed. When the mode change line at the time of low accelerator pedal opening is crossed while the target through speed ratio Ith * is not changed, the sub-transmission 31 starts upshifting, and the variator CVT starts downshifting. At this time, the transmission controller 24 receives engine torque information from the engine controller 22, and is in a power-on state (hereinafter referred to as P / ON) or a power-off state (hereinafter referred to as P / OFF). In the case of P / ON, when the sub-transmission 31 is upshifted, the engine blow-up due to the torque phase is prevented, and then the inertia phase is started. On the other hand, at the time of P / OFF, since there is no possibility that the engine 1 will blow up, when the sub-transmission 31 is upshifted, it starts from the inertia phase. That is, the timing at which the inertia phase starts differs between P / ON and P / OFF.

  Next, in the vicinity of zero torque where it is difficult to determine P / ON and P / OFF, the determination of P / ON and P / OFF may be wrong. If P / ON is erroneously determined in the P / OFF state, the inertia phase starts at the time of the torque phase, and the shift start timing of the variator CVT is delayed from the progress of the shift of the sub-transmission 31. As a result, the through speed ratio Ith shifts to the high side, and the engine speed Ne decreases, so that the lockup clutch needs to be released, which may lead to deterioration in fuel consumption.

  Therefore, in the first embodiment, the following configuration is adopted in an area where there is a possibility that P / ON and P / OFF may be erroneously determined. Here, an area in which P / ON and P / OFF may be erroneously determined is defined. As shown in the shift map of FIG. 3, from the viewpoint of the vehicle speed VSP, the definition of the mode switching line at the time of the high accelerator pedal opening is less than or equal to the vehicle speed V2, and the mode switching line at the time of the low accelerator pedal opening is defined. It was decided that the vehicle speed range was higher than the starting vehicle speed V1 (<V2). Next, from the viewpoint of the turbine rotation speed Nt, the high speed mode lowest line and the coast line among the mode switching lines at the time of the low accelerator pedal opening, which is a region on the higher rotation side than the rotation speed where the coast line is set. The vehicle speed V3 intersects with the turbine speed Nt defined by the low-accelerator pedal opening mode switching line and is a region slightly lower than the turbine speed N1. Here, among the above-described regions, a region surrounded by V3 and V2 is denoted by Z1, and a region surrounded by V1 and B3 is denoted by Z2. When it is in the area of either Z1 or Z2, it is an area where erroneous determination of P / ON and P / OFF is likely to occur.

  Then, in the areas Z1 and Z2 in which P / ON and P / OFF may be erroneously determined, it is always determined as P / OFF. Thereby, the progress of the shift in the torque phase can be avoided. Since the torque is in the vicinity of zero, the engine speed does not blow up even if P / OFF is determined.

  FIG. 5 is a time chart showing a speed change state when a low accelerator pedal opening mode switching line is crossed by releasing the accelerator pedal in the vehicle of the comparative example. In this case, the target gear ratio is also changed to the upshift side by a change in the accelerator pedal opening APO. At this time, the target through speed ratio Ith * is also changed.At the same time, the variator CVT initially performs an upshift, but the sub-transmission 31 starts an upshift because it crosses the mode switching line at the time of low accelerator pedal opening. The variator CVT begins a downshift. At this time, since the shift speed of the variator CVT is slow, if the downshift after the upshift is performed, the through speed ratio is shifted to the High side due to the delay of the shift of the variator CVT, so that the engine speed decreases.

  Therefore, in the first embodiment, in the regions Z1 and Z2, the speed of change of the target through speed ratio Ith * is slowed down and the cooperative shift is interrupted, and the shift of the sub-transmission 31 and the shift of the variator CVT are executed independently. It was decided to. Therefore, because the target through speed ratio Ith * becomes slow, the variator CVT does not upshift so much in the first stage.Therefore, when the downshift is performed when crossing the mode switching line at the time of low accelerator pedal opening. The amount of change can be reduced. Therefore, even when the speed of the variator CVT is low, the downshift delay can be suppressed. Also, since the coordinated shift is stopped and the subtransmission 31 and the variator CVT are shifted independently, the shift on the variator CVT side can be started immediately without waiting for the start of the inertia phase of the subtransmission 31. It is possible to avoid shifting the through speed ratio Ith to the high side. Therefore, even if the shift speed of the target through speed ratio Ith * is slowed down, the variator CVT can be sufficiently downshifted when the inertia phase of the auxiliary transmission 31 ends. Note that the shift speed of the target through speed ratio Ith * is set to be slower than that of the area Z2, since the shift speed of the area Z1 is slower.

FIG. 6 is a flowchart illustrating an upshift process by straddling the mode switching line according to the first embodiment.
In step S1, it is determined whether or not the operating point of the automatic transmission 4 is in the region Z1 or Z2. If YES, the process proceeds to step S5, and if NO, the process proceeds to step S2.
In step S2, it is determined whether it is P / ON or P / OFF. If P / ON, the process proceeds to step S3 to execute P / ON upshift processing. On the other hand, in the case of P / OFF, the process proceeds to step S4 to execute the P / OFF upshift process. Since the area other than Z1 or Z2 is an area in which erroneous determination of whether it is P / ON or P / OFF is unlikely to occur, normal processing is performed.

In step S6, the speed at which the target through speed ratio Ith * is set is set to VG1.
In step S7, the speed at which the target through speed ratio Ith * is set is set to VG2, which is faster than VG1.
In step S8, an upshift process at low rotation is executed. Specifically, P / OFF is set regardless of the information content from the engine controller 22, the cooperative shift is stopped, and the independent shift is performed.

  FIG. 7 is a time chart showing a shift state when the low accelerator pedal opening mode switching line is crossed by releasing the accelerator pedal opening in the vehicle of the first embodiment. When the driver releases the accelerator pedal, the target through speed change ratio Ith * is changed. At this time, the speed is set to be slower than the target through speed ratio Ith * (the one-dot chain line shown in the comparative example in FIG. 7) set in another region. Further, since the coordinated shift is stopped, the variator CVT starts the shift immediately. Although the upshift is performed at first, the upshift is not performed so much because the shift speed is set to be slow. Further, when the sub-transmission 31 starts upshifting, upshifting is performed at P / OFF, so that the shift timing does not vary. Further, after the sub-transmission 31 starts upshifting, the variator CVT starts downshifting. However, since the variator CVT is not so upshifted, the amount of downshifting can be reduced. In addition, because there is no coordinated shift, the variator CVT quickly downshifts assuming that the subtransmission 31 has started the inertia phase, so the variator CVT downshifts before the upshift of the subtransmission 31 is completed. Since it completes, the fall of engine speed Ne can be suppressed.

As described above, in the first embodiment, the following operational effects can be obtained.
(1) An automatic transmission 4 having a variator CVT (main transmission mechanism) capable of continuously changing the transmission gear ratio and a sub-transmission 31 (sub-transmission mechanism) having a plurality of fixed gears; The target through speed ratio Ith * (target speed ratio) is calculated, and the variator CVT and the sub-transmission ratio so as to achieve the target through speed ratio Iv * by combining the variator speed ratio Iv of the variator CVT and the speed ratio Isub of the subtransmission 31. A transmission controller 24 for controlling a transmission ratio of the transmission 31, and the transmission controller 24 determines whether the input torque of the automatic transmission 4 is in a power-on state or a power-off state based on torque information received from the engine 1. In the power-on state, power-on upshift control is performed to shift from the torque phase to the inertia phase when the subtransmission 31 is upshifted. When the speed gear 31 is upshifted, power off upshift control is performed to shift from the inertia phase to the torque phase, and a mode switching line at the time of low accelerator pedal opening (the first shift mechanism that upshifts the auxiliary transmission mechanism at the low accelerator pedal opening). More than V1 (first vehicle speed) where the 1-mode switching line) is set, a mode switching line at the time of high accelerator pedal opening (second mode switching line for upshifting the auxiliary transmission mechanism at the high accelerator pedal opening) is set. The vehicle speed range is less than V2 (second vehicle speed), which is equal to or higher than the turbine speed of the coast line (the main transmission mechanism input speed) where the target through speed ratio Ith * for coasting is set, and is low accelerator. V3 (third car) where the coast line intersects the high-speed mode lowest line (lowest line when the sub-transmission mechanism selects the high gear) among the mode switching lines when the pedal is open. ) When the sub-transmission 31 is upshifted in the regions Z1 and Z2 (first region) defined by the rotational speed range of the turbine rotational speed N1 or less corresponding to the mode switching line at the time of the low accelerator pedal opening in FIG. Power-off upshift control is performed regardless of information.
Therefore, regardless of the power-on or power-off determination result, it is possible to suppress a decrease in the engine speed Ne accompanying an upshift of the sub-transmission 31, and to suppress the release of the lock-up clutch, thereby suppressing fluctuations in vehicle behavior. it can.

(2) When the transmission controller 24 upshifts the sub-transmission 31 in the regions Z1 and Z2, the transmission controller 24 makes the change speed of the target through speed ratio Ith * slower than the change speed in the regions other than the areas Z1 and Z2.
Therefore, even when the gear change speed of the variator CVT is slow, it is possible to suppress a decrease in the engine speed Ne.

(3) The transmission controller 24 further slows down the changing speed of the target through speed ratio Ith * in the area Z2 (in the first area and not more than the third vehicle speed).
Therefore, even if the speed change speed of the variator CVT is slower, it is possible to suppress a decrease in the engine speed Ne.

1 Engine (power source)
2 Electric motor (power source)
3 Starter motor
4 V belt type continuously variable transmission
5 Drive wheels
6 Primary pulley
7 Secondary pulley
8 V belt
CVT variator (continuously variable transmission)
T / C torque converter
9 Final gear set
19 Accelerator pedal
22 Engine controller
24 Transmission controller
27 Accelerator pedal opening sensor
O / P oil pump
31 Sub-transmission
CL clutch
H / C high clutch
R / B reverse brake
L / B Low brake
32 Vehicle speed sensor

Claims (3)

An automatic transmission having a main transmission mechanism capable of continuously changing a transmission gear ratio, and an auxiliary transmission mechanism having a plurality of fixed shift stages;
A target transmission ratio of the automatic transmission is calculated, and the main transmission mechanism and the auxiliary transmission mechanism are configured to achieve the target transmission ratio by combining the transmission ratio of the main transmission mechanism and the transmission ratio of the auxiliary transmission mechanism. A controller for controlling the transmission ratio;
With
The controller determines whether the input torque of the automatic transmission is in a power-on state or a power-off state based on torque information received from the engine, and upshifts the auxiliary transmission mechanism in the power-on state. Power on upshift control to shift from torque phase to inertia phase, and power off upshift control to shift from inertia phase to torque phase when upshifting the auxiliary transmission mechanism when power off ,
A second mode switching line for upshifting the auxiliary transmission mechanism at a high accelerator pedal opening is set at a speed higher than the first vehicle speed at which the first mode switching line for upshifting the auxiliary transmission mechanism at a low accelerator pedal opening is set. In the vehicle speed range equal to or lower than the second vehicle speed, which is equal to or higher than the input speed of the main transmission mechanism of the coast line in which the target speed ratio during coasting is set, Rotational speed equal to or less than the main transmission mechanism input rotational speed according to the first mode switching line at the third vehicle speed at which the lowest line and the coast line intersect when the auxiliary transmission mechanism selects the high gear. In the first region defined by the region, when the sub-transmission mechanism is upshifted, the power-off upshift control is performed regardless of the torque information. The control apparatus for an automatic transmission according to claim 1,
The controller, when upshifting the sub-transmission mechanism in the first region, makes the change speed of the target gear ratio slower than the change speed when outside the first region. Control device. The control apparatus for an automatic transmission according to claim 2,
The controller of an automatic transmission, wherein the controller further reduces the change speed when the speed is within the first region and is equal to or lower than the third vehicle speed.

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